The various blood processing systems now make it possible to collect and/or process particular blood constituents, instead of whole blood, from a blood source such as, but not limited to, a container of previously collected blood or other living or non-living source. Typically, in such systems, whole blood is drawn from a blood source, a particular blood component or constituent is separated, removed, and collected, and the remaining blood constituents are returned to the blood source. Removing only particular constituents is advantageous when the blood source is a human donor, because potentially less time is needed for the donor's body to return to pre-donation levels, and donations can be made at more frequent intervals than when whole blood is collected. This increases the overall supply of blood constituents, such as plasma and platelets, made available for transfer and/or therapeutic treatment.
Whole blood is typically separated into one or more of its constituents (e.g., red cells, platelets, and plasma) by processing through a disposable fluid flow circuit that is associated with a durable, reusable device that controls the processing of fluid through the flow circuit by a variety of pumps, valves, sensors and the like that operate on the fluid flow circuit. Typical separation techniques include centrifugation, such as in the AMICUS® separator from Fenwal, Inc., of Lake Zurich, Ill., or other centrifugal separation devices, or membrane separation such as a spinning membrane-type separator, such as the AUTOPHERESIS-C® and AURORA devices from Fenwal, Inc.
While the above refers to apheresis systems in particular, the present subject matter, as seen below, is not limited to such whole blood apheresis applications but may include systems for processing blood components or other biological fluid components. With reference to apheresis systems, as noted above, blood components that are not collected are typically returned to the source or subject, such as a patient or donor. These may include concentrated red cells, plasma, platelets or some combination of these. Also, it is common to infuse into the donor or patient a replacement fluid, such as saline, to replace the volume of the blood components that have been removed and not returned. To this end, such systems include a fluid flow path that communicates with the source or subject, such as but not limited to a human donor or patient, for directing or returning blood, blood components or other fluids to the subject. The fluid flow path is usually in the form of flexible plastic flow tubing terminating in a needle or other access device that is inserted into a subject's (human donor's or patient's) vein.
Systems of the type described above often include sensors and/or detectors that monitor various aspects of the biological fluid processing procedure as well as system performance and operation. When necessary, in response to a sensed or detected abnormal condition, the system may generate an alarm or an alert informing the operator of the specific condition. Some conditions may require termination of the biological fluid processing procedure. Others may require some form of operator intervention, correction, and/or acknowledgement.
There are, however, still other conditions that cannot be corrected by the operator. For example, certain errors detected in the hardware cannot be corrected by the operator. Examples of such hardware errors include pump and spinner rate errors (e.g., if the spinner is spinning too fast, too slow, is stalled, is not changing rates, is not stopping fast enough, or the direction of spin is reversed); clamps that do not open/close when intended; disturbances on the weight scales that increase signal variation/noise, but do not affect the average reading; inflation of the pressure cuff for a long period of time; readings of the pressure sensors that are outside of the normal range, but not hazardous; analog-to-digital conversions that did not complete as expected. Many such errors are not critical to the performance of the device or the processing of the biological fluid provided that they do not persist beyond a certain threshold and do not pose a threat to the safety of the patient/donor.
Generally, an alert or an alarm requiring operator action, even such as operator acknowledgment of an alarm, adds time to the fluid processing procedure. This can be particularly undesirable where one operator is monitoring several procedures being performed on several devices at the same time such as in a blood center or other facility. Thus, it would be particularly advantageous to provide a system whereby processing can resume even in view of a certain (low) level or category of hardware error without the need for operator intervention, nor acknowledgment, nor a complete termination of the procedure. The methods and systems of the present disclosure are particularly advantageous where the only operator action is to resume the procedure and monitor for recurrence of the same issue. In accordance with the present disclosure, the system can carry out and complete this action automatically and independently of the operator. The subject matter of the present disclosure addresses these and other needs.